Neurophysiology of Visual Perception

视觉感知的神经生理学

• 批准号: 9568260
• 负责人: David A Leopold
• 金额: $ 46.01万
• 依托单位: NATIONAL INSTITUTE OF MENTAL HEALTH
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/9568260
• 关键词: Ablation; Adult; Affect; Area; Attention; Behavior; Blinking; Brain; Callithrix; Cell Nucleus; Complex; Cues; Darkness; Data Analyses; Development; Dimensions; Distant; Electrodes; Electrophysiology (science); Elements; Environment; Esthesia; Event; Evolution; Eye; Eye Movements; Faculty; Functional Magnetic Resonance Imaging; Human; Image; Individual; Laboratories; Life; Light; Macaca; Mammals; Manuals; Maps; Measures; Mental disorders; Methods; Modeling; Molds; Motion; Nervous system structure; Neurons; Paper; Parietal Lobe; Pathway interactions; Patients; Pattern; Perception; Persons; Positioning Attribute; Preparation; Primates; Process; Publishing; Pulvinar structure; Research; Resolution; Retina; Retinal; Role; Semantics; Series; Shapes; Signal Transduction; Stimulus; Structure; Surface; Thalamic Nuclei; Thalamic structure; Time; Vision; Vision Disparity; Visual; Visual Cortex; Visual Pathways; Visual Perception; Work; area V1; area striata; experience; experimental study; extrastriate visual cortex; impression; interest; movie; nervous system disorder; neurophysiology; nonhuman primate; novel; postnatal; programs; receptive field; relating to nervous system; remote sensing; response; two-dimensional; visual information

To understand our vision, it is critical to place humans within an appropriate phylogentic context: humans are primates, and their dominant use of vision is typical of primates and different from other mammals. As a sensing faculty, vision places individuals at a great advantage over their environment, allowing them to remotely sense complex details from a safe distance. As this context is critical for our research, we recently published a comprehensive review describing the distinguishing features of primate vision against a mammalian background, and thus placing human vision into its proper evolutionary context (Leopold, Freiwald, and Mitchell, Evolution of Nervous Systems, ed. Kaas, 2017). Much of our research on visual perception centers on how we see shapes, objects, and scenes. From the moment light enters the eyes, our percept is molded by a series of processing stages, crafted through years of visual experience during primates unusually long period of development. In our laboratory, we combine fMRI and electrophysiology to ask questions such as, how does the brain create a three-dimensional representation of the world, given that its retinal images are inherently two-dimensional? How do we complete surfaces, distinguish between foreground and background, and understand the difference between real motion and the motion caused by our own eye movements? These types of questions are present in each of our research lines. Here we described several studies that focus on particular sub-questions. In the past two years, we have placed most of our emphasis studying visual perception on the mysterious role of the large pulvinar nucleus of the thalamus, which projects to multiple visual areas including the primary visual cortex (V1). In one set of studies, we have been investigating electrical activity across the pulvinar using a novel electrode mapping approach. This large project has yielded two papers currently in preparation (Murphy et al. and (Deng et al.. We have recently published a comprehensive review paper on the pulvinar, (Bridge et al., 2016), which focuses on multiple aspects of its structure and function, including a newly hypothesized transient visual pathway that precedes that adult geniculostriate pathway that conveys early postnatal visual information. We have recently submitted a large collaborative study investigating the role of early-life ablation of one small pulvinar nucleus, and the effect of its disruption on visually-guided manual behavior in the adult (Mundinano et al., 2017), under review. We have also made progress on activity in the visual cortex, focusing on several features of area V1. In one study, currently under review (Cox et al., 2017)), we have studied the effects of a brief attentional cue on activity outside neurons receptive fields within V1, with the results suggesting that there is effectively an activity blink just following the presentation of meaningful cues. We further investigated the entrainment of spiking and gamma-range LFP activity by alpha signals (Dougherty et al., 2017). We also published a paper showing that the ablation of are V1 does not disrupt but rather enhances activity correlation in higher-order visual areas (Shapcott et al., 2016). Finally, in a collaborative study, we found that human patients with damage to the parietal cortex were selectively affected in their perception of binocular disparity (Murphy et al., 2016). In our work on visual perception, we have been increasingly interested in the brains responses to stimuli that are not simply flashed on the screen but that rather evolve over time. To this end, we have conducted multiple studies in which macaques and marmosets freely view dynamic video stimuli. From an experimental perspective, data analysis from this type of experiment can be challenging, as there is inherent variability in the subjects eye positions. In one study, we systematically examined the regional fMRI responses to the subjects eye movements, and compared them to the fMRI responses to the events in the movie itself (Russ et al., 2016). We found that the activity patterns under these two conditions were very different. In a very recent study, we used both fMRI and electrophysiology to create a new means to classify neural responses using fMRI maps (Park et al., 2017). This method demonstrated that neurons within hundreds of microns of one another were affiliated in very different ways with distant brain areas. These and other results from the natural viewing paradigm have raised a number of new questions about how the brain interprets its retinal images, and we are currently in the process of focusing on the temporal dynamics of the responses, asking to what extent neural responses integrate temporal integration over time (Russ et al., in preparation).

要了解我们的视野，将人类放置在适当的系统态环境中至关重要：人类是灵长类动物，并且他们对视力的主要使用是灵长类动物的典型，并且与其他哺乳动物不同。 作为一种感应的教师，视觉使个人比环境具有很大的优势，从而使他们从安全的距离中远程感知复杂的细节。 由于这种背景对于我们的研究至关重要，我们最近发表了一项全面的综述，描述了灵长类动物视野对哺乳动物背景的区别特征，从而将人类的视力置于其适当的进化环境中（Leopold，Freiwald和Mitchell，Minter System的进化，神经系统的进化，Ed。Kaas，2017）。 我们对视觉感知的大部分研究集中在我们如何看待形状，对象和场景的方式上。从光进入眼睛的那一刻，我们的感知是由一系列的处理阶段塑造的，这些阶段是通过多年的图像经验在异常长时间长时间开发的过程中制成的。在我们的实验室中，我们将功能磁共振成像和电生理学结合起来，提出诸如大脑如何创建世界三维表示的问题，因为它的视网膜图像本质上是二维的？我们如何完成表面，区分前景和背景，并了解真实运动与由我们自己的眼动引起的运动之间的差异？这些类型的问题都存在于我们的每个研究线中。在这里，我们描述了几项关注特定子问题的研究。 在过去的两年中，我们将大多数重点研究视觉感知对丘脑的大脉冲核的神秘作用进行了研究，后者将其投影到包括主要视觉皮层（V1）在内的多个视觉区域。 在一组研究中，我们一直在使用一种新型的电极映射方法来研究整个脉冲的电活动。 这个大型项目已经制定了两篇论文（Murphy等人和（Deng等人。我们最近发表了一份有关Pulvinar的综合审查论文（Bridge等，2016），（Bridge等，2016），重点介绍其结构和功能的多个方面，其中包括一个新的假设的瞬态途径，该途径是成人近期探测的早期信息，该途径始终是一定的，该探测范围是一定的。研究了一个小牙骨核的早期消融的作用，以及其破坏对成人视觉引导的手动行为的影响（Mundinano等，2017），正在综述中。 我们还在视觉皮层的活动中取得了进展，重点是区域V1的几个特征。在目前正在综述的一项研究中（Cox等人，2017年）），我们研究了简短的注意提示对V1内神经元接受的活动的影响，结果表明，在有意义的提示呈现后，有效的活动闪烁。 我们进一步研究了α信号夹带尖峰和伽马范围LFP活性（Dougherty等，2017）。我们还发表了一篇论文，表明V1的消融不会破坏，而是增强了高阶视觉区域的活动相关性（Shapcott等，2016）。最后，在一项合作研究中，我们发现对顶叶皮层损害的人类患者在对双眼差异的看法方面有选择地影响（Murphy等，2016）。 在我们的视觉感知工作中，我们对不仅在屏幕上闪烁的刺激的大脑反应越来越感兴趣，而且随着时间的流逝而发展。 为此，我们进行了多项研究，其中猕猴和桃花心可以自由观看动态视频刺激。从实验的角度来看，这类实验的数据分析可能具有挑战性，因为受试者眼睛位置存在固有的可变性。 在一项研究中，我们系统地检查了对受试者眼动的区域功能磁共振成像的反应，并将其与对电影本身事件的fMRI响应进行了比较（Russ等，2016）。 我们发现，这两种情况下的活动模式大不相同。 在最近的一项研究中，我们同时使用fMRI和电生理学来创建一种使用fMRI MAPS对神经反应进行分类的新方法（Park等，2017）。 该方法表明，彼此之间数百微米以内的神经元与遥远的大脑区域相关。 自然观看范式的这些结果和其他结果提出了许多有关大脑如何解释其视网膜图像的新问题，我们目前正在关注响应的时间动态，询问神经反应在多大程度上将时间整合随时间纳入时间（Russ等人，在准备中）。